Port length changes by switching height and width?

I was messing around with a port length calculator and noticed than when using all the same numbers, but switching the port height and width dimensions, that it would give two considerably different port lengths.

I don't know much about this and am trying to learn. Why does the vent length change when switching the width and height? The port square inches doesn't change is why this confuses me. If anyone could explain why it would sure be a help.